This invention relates to root crop harvesting equipment and more particularly to the blade assemblies that are utilized with such equipment for disengaging and lifting the root crop upwardly from their subsoil elevations.
Although harvesting of potatoes or other root crops has been considerably automated, it has been difficult to provide a harvester mechanism that is capable of delicately handling the crop without inflicting damage thereto. Studies have shown that in some parts of the United States approximately 10 percent of potato tubers are rejected as Number One Grade because of damage caused by harvesting equipment. This represents an annual loss in millions of dollars. Much of the harvesting injury is caused as the potatoes or other root crop is being disengaged from its subsoil environment.
In my previous application, now U.S. Pat. No. 3,625,290, I disclosed and claimed a new and useful separating apparatus for mobile potato harvesting vehicles that has proved to be very effective in reducing the amount of harvester damage to the harvested root crop. In the disclosure, I describe a vibrating digging means that is suspended on the supporting harvester framework for digging into the soil to lift both root crop and foreign material above the ground level onto a conveying mechanism. The vibration is produced about a horizontal axis spaced substantially rearward from the ground engaging blade. Primarily, the purpose of the vibrating motion was to produce rearward movement of the root crop onto the conveyor assembly. The present invention was designed as a substantial improvement over the vibrating digging means as set out in my prior patent. Through the present invention, not only is the root crop moved upward and rearwardly by the oscillating blade assembly, but the blade assembly is moved in such a manner as to loosen the soil forward of the blade assembly and therefore prevent undesired engagement and damage to the root crop forward of the leading blade edge as the implement is moved along.
The blade disclosed herein is unobstructed the full width of the machine, illustrated in a full two row width. The blades previously developed by me used a separate blade for each row and required pivot arms in the center of the machine, which was located along the furrow between two dug rows. The center arms presented an additional obstruction on which vines and trash could collect. It also made it impossible to dig windrowed potatoes, which are typically dug along two adjacent rows and placed in the furrow between them.